2,3,5,6-四氨基吡嗪的合成

Synthesis of 2, 3, 5, 6-Tetraaminopyrazine

摘要:

以亚氨基二乙腈为起始原料，经亚硝化、环合、硝化、还原四步反应得到2,3,5,6-四氨基吡嗪（TAPA），结构经NMR，IR，ESI-MS确证，总产率达到26.8%。分别探讨了环合反应温度及不同的硝化体系对中间产物中间产物Ⅲ和Ⅳ收率的影响，并讨论了加氢还原反应的影响因素，得出最佳工艺条件为：环合反应温度为25℃；硝化反应中，选择硝酸钾和发烟硫酸作为硝化体系；还原反应中，m(Pd/C):m(2,6-二氨基-3,5-二硝基吡嗪-1-氧化物)=1:15，V(CH3OH):V(H2O)=1:1，反应温度为55℃，氢气压力在0.8～1.2MPa之间。该合成路线的优点在于起始原料亚氨基二乙腈廉价易得，中间体易于保存，因而大幅度降低了生产成本。

Abstract:

2,3,5,6-tetraaminopyrazine (TAPA) was synthesized from iminodiacetonitrile through nitrosation, cyclization, nitration and reduction. The structure of the target product as well as that of the intermediates of each reaction was confirmed by NMR, IR, ESI-MS. The overall yield was 26.8%. The effects of different cyclization reaction temperatures and nitration systems on the yields of intermediates were investigated respectively. In addition, the influence factors of hydrogenation reduction reaction were discussed. The optimal conditions were determined as follows: The temperature of cyclization reaction was 25℃;In the nitration reaction, the best system of nitration was selected as KNO3 and fuming H2SO4; In the reduction reaction, the mass ratio of Pd/C to 2,6-diamino-3,5-dinitropyrazine-1-oxide was 1:15, the best solvent system was selected as CH3OH and H2O (volume ratio 1:1), the reaction temperature was 55℃ and hydrogen pressure was in 0.8～1.2MPa . The advantages of this new synthetic route were that the starting material was commercially available and that the intermediates had good stability, which can reduce the cost of synthesis greatly.